1. Field of the Invention
The present invention relates to cold-formable laminate films containing a barrier layer that is impermeable to water vapour and gases and, on both sides of the barrier layer, at least one plastic layer; it also relates to the use of the laminate films.
2. Background Art
Known from EP-A 0 845 350 are cold formable laminate films e.g. for so called blister packs or push through packs. Described there are plastic laminates containing a metal foil which are deepened in such a manner that a plurality of recesses or cups results. Shoulders are formed between the individual recesses. The shoulders run completely round each recess and form a flat shoulder area. The materials prepared this way form the base part of a blister pack. The base parts may be filled with substances i.e. the contents. Known contents for blister packs are e.g. tablets, capsules, dragees etc., from the pharmaceutical field, single or if desired having more than one in each recess. After that, the base part is closed off by sealing a lidding foil such as a metal foil--usefully aluminium foil or a laminate containing e.g. a sealing layer and a metal foil--on to the shoulders of the base part by means of the sealing layer.
The described laminate films exhibit good formability. The ratio of the recesses of a blister pack diameter to depth may be selected within a wide range i.e. the walls of the recesses may exhibit a low or high degree of steepness. There is however the need to have laminate films whose formability can be improved even further. Laminate films with much improved formability are in demand e.g. in the field of medical instruments and applicators.